1. Field of the Invention
The present invention relates to a method for fabricating a thin film touch screen panel.
2. Description of the Related Art
A touch screen panel is an input device capable of inputting a command of a user by a touch of a specific position displayed on a screen of an image display device, etc., with a finger of the user or an object such as a touch pen or a stylus pen.
For this, in the image display device provided with the touch screen panel on a front face thereof, a force applied to the contact position by a direct touch with the finger of a user or the object is converted to an electrical signal. Therefore, an instruction corresponding to the contact position selected by the user is input to the image display device as an input signal generated by the electrical signal.
Since a separate input device such as a keyboard and a mouse which are connected to the image display device to input an operation command may be replaced by the above-described touch screen panel, it is a recent trend to gradually enlarge the application fields of the touch screen panel.
Various types of touch screen panel such as a resistive film type, surface acoustic wave type using an infrared or ultrasonic wave, capacitance touch type, or the like, are known in the related art for implementing the touch screen panel. Among these, in the capacitance type touch screen panel, when the finger of a user or the object touches a specific position displayed thereon, a change in capacitance formed by conductive sensing patterns with adjacent other sensing patterns or a ground electrode is detected by the image display device equipped with the touch screen panel, and thereby a force applied to the contact position is converted to an electrical signal.
Generally, the above-described touch screen panel is adhered on an outer surface of a flat panel display device such as a liquid crystal display device, or an organic electroluminescence display device to be commercialized in many cases. Accordingly, the touch screen panel needs to have characteristics such as a high transparency and a small thickness.
Recently, a flexible flat panel display device has been developed, and in accordance with this trend, it is necessary for the touch screen panel adhered on the flexible flat panel display device to have flexible characteristics.
However, the capacitance type touch screen panel needs a thin film deposition, pattern formation process, or the like, in order to form sensing patterns, etc., for implementing a touch sensor. Therefore, characteristics such as high heat resistance and chemical resistance, or the like are required. Accordingly, the capacitance type touch screen panel is provided with a transparent electrode laminate which is formed on a base film by applying a resin such as a polyimide resin having excellent heat resistance and curing the same.
On the other hand, such a thin and flexible base film may be easily bent or distorted. Therefore, it is difficult to handle the base film during a manufacturing process thereof, and form the transparent electrode laminate.
As a solution for solving the above-described problem, a method including the processes of forming an adhesive layer on a glass and adhering a base film thereon, and forming a transparent electrode laminate on the base film, and then delaminating the base film from the glass has been proposed. However, in such a case, since the adhesive layer is contracted and/or expanded by thermal and physical energy applied thereto during the adhesive layer forming process and the adhering process, the glass is bent, and thereby it is also difficult to form the transparent electrode laminate similar to as described above.
For example, Korean Patent Laid-Open Publication No. 2012-133848 discloses a flexible touch screen panel with no proposal for solving the above-described problems.